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                | Author |  Topic  |           |  
                | kimikimono
 
                1 Posts | 
                    
                      |  Posted - 12/22/2010 :  5:47:39 PM           
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                      | Origin Ver. and Service Release (Select Help-->About Origin): 8.0 SR0 Operating System:W7
 Hello everybody
  I'm trying to fit peak curves with the following expressions:
 y=((2*3,1416*(ct-1))^(-0,5))*x/exp((-(x-1)^2)/(2*(ct-1))), and
 y=ln((x*(ct^(0,5))/(x*ln(ct))))*((ct/(2*3,1416*ln(ct)))^(0,5))*(exp(-0,5*(ln(x*(ct^0,5)))^2)/(ln(ct)))/(exp(0,5*ln(ct))),
 being just y=f(x) and ct a constant value that I must set, not even iterate it...
 Those functions should work since I actually obtained "y" data from them (then, this is a double-checking for the equations). Nor the curve-fitting tool neither the simulation works
 Any clue???
 Thanks a lot
 Jose
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                | minimax
 
                363 Posts | 
                    
                      |  Posted - 12/29/2010 :  07:45:29 AM           
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                      | Hi Jose, 
 Comma can not be used as numeric separator in function definition in any OS.
 
 You need to use dot "." instead, like
 
 y=((2*3.1416*(ct-1))^(-0.5))*x/exp((-(x-1)^2)/(2*(ct-1)))
 y=ln((x*(ct^(0.5))/(x*ln(ct))))*((ct/(2*3.1416*ln(ct)))^(0.5))*(exp(-0.5*(ln(x*(ct^0.5)))^2)/(ln(ct)))/(exp(0.5*ln(ct)))
 
 Max
 OriginLab Technical Support
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